<?phpclass LowercasePipe extends BasePipe{	private $field;	private $result_field;		public function __construct($config)	{		parent::__construct($config);		$this->field = $config["field"];		$this->result_field = $config["result_field"];	}		public function transform_record($record)	{		$field = $this->field;		$result_field = $this->result_field;				$result = $this->cache->recover_record($record->$field);		if ($result !== null)		{			$this->logger->log_debug("Retrieving result from cache");			$record->$result_field  = $result;		}		else		{			$record->$result_field = strtolower($record->$field);			$this->logger->log_debug("Saving result to cache");			$this->cache->cache_record($record->$field, $record->$result_field);		}				return $record;	}}